feat(codegen): minify string with backtick when needed (#8095)

oxc-project · Dec 24, 2024 · 0562830 · 0562830
1 parent ad2a620
commit 0562830
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Showing 3 changed files with 39 additions and 20 deletions.
diff --git a/crates/oxc_codegen/src/gen.rs b/crates/oxc_codegen/src/gen.rs
@@ -1375,31 +1375,27 @@ fn print_unquoted_str(s: &str, quote: u8, p: &mut Codegen) {
             }
             '\'' => {
                 if quote == b'\'' {
-                    p.print_str("\\'");
-                } else {
-                    p.print_str("'");
+                    p.print_ascii_byte(b'\\');
                 }
+                p.print_ascii_byte(b'\'');
             }
             '\"' => {
                 if quote == b'"' {
-                    p.print_str("\\\"");
-                } else {
-                    p.print_str("\"");
+                    p.print_ascii_byte(b'\\');
                 }
+                p.print_ascii_byte(b'"');
             }
             '`' => {
                 if quote == b'`' {
-                    p.print_str("\\`");
-                } else {
-                    p.print_str("`");
+                    p.print_ascii_byte(b'\\');
                 }
+                p.print_ascii_byte(b'`');
             }
             '$' => {
-                if chars.peek().is_some_and(|&next| next == '{') {
-                    p.print_str("\\$");
-                } else {
-                    p.print_str("$");
+                if chars.peek() == Some(&'{') {
+                    p.print_ascii_byte(b'\\');
                 }
+                p.print_ascii_byte(b'$');
             }
             // Allow `U+2028` and `U+2029` in string literals
             // <https://tc39.es/proposal-json-superset>
@@ -1424,22 +1420,40 @@ impl Gen for StringLiteral<'_> {
         let quote = if p.options.minify {
             let mut single_cost: u32 = 0;
             let mut double_cost: u32 = 0;
-            for b in s.as_bytes() {
+            let mut backtick_cost: u32 = 0;
+            let mut bytes = s.as_bytes().iter().peekable();
+            while let Some(b) = bytes.next() {
                 match b {
+                    b'\n' if p.options.minify => {
+                        backtick_cost = backtick_cost.saturating_sub(1);
+                    }
                     b'\'' => {
                         single_cost += 1;
                     }
                     b'"' => {
                         double_cost += 1;
                     }
+                    b'`' => {
+                        backtick_cost += 1;
+                    }
+                    b'$' => {
+                        if bytes.peek() == Some(&&b'{') {
+                            backtick_cost += 1;
+                        }
+                    }
                     _ => {}
                 }
             }
+            let mut quote = b'"';
             if double_cost > single_cost {
-                b'\''
-            } else {
-                b'"'
+                quote = b'\'';
+                if single_cost > backtick_cost {
+                    quote = b'`';
+                }
+            } else if double_cost > backtick_cost {
+                quote = b'`';
             }
+            quote
         } else {
             p.quote
         };

diff --git a/crates/oxc_codegen/tests/integration/unit.rs b/crates/oxc_codegen/tests/integration/unit.rs
@@ -38,6 +38,11 @@ fn expr() {
 
     test("delete 2e308", "delete (0, Infinity);\n");
     test_minify("delete 2e308", "delete(1/0);");
+
+    test_minify(
+        r#";'eval("\'\\vstr\\ving\\v\'") === "\\vstr\\ving\\v"'"#,
+        r#";`eval("'\\vstr\\ving\\v'") === "\\vstr\\ving\\v"`;"#,
+    );
 }
 
 #[test]

diff --git a/tasks/minsize/minsize.snap b/tasks/minsize/minsize.snap
@@ -5,7 +5,7 @@ Original   | minified   | minified   | gzip       | gzip       | Fixture
 
 173.90 kB  | 61.55 kB   | 59.82 kB   | 19.54 kB   | 19.33 kB   | moment.js 
 
-287.63 kB  | 92.60 kB   | 90.07 kB   | 32.27 kB   | 31.95 kB   | jquery.js 
+287.63 kB  | 92.59 kB   | 90.07 kB   | 32.28 kB   | 31.95 kB   | jquery.js 
 
 342.15 kB  | 121.55 kB  | 118.14 kB  | 44.64 kB   | 44.37 kB   | vue.js    
 
@@ -21,7 +21,7 @@ Original   | minified   | minified   | gzip       | gzip       | Fixture
 
 3.20 MB    | 1.02 MB    | 1.01 MB    | 332.00 kB  | 331.56 kB  | echarts.js
 
-6.69 MB    | 2.39 MB    | 2.31 MB    | 495.63 kB  | 488.28 kB  | antd.js   
+6.69 MB    | 2.39 MB    | 2.31 MB    | 495.62 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.54 MB    | 3.49 MB    | 909.72 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.54 MB    | 3.49 MB    | 909.73 kB  | 915.50 kB  | typescript.js